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Abstract: The photocatalytic destruction of organic substances is an efficient method for the production of high-quality purified water for various applications. For photocatalytic purposes, titania is most widely studied due to its low cost, availability, untoxicity, and stable chemical structure. The combined application of a photocatalyst and hydrogen peroxide increases the degree of ecotoxicants destruction to CO2, H2O, and inorganic ions (mineralization) and shortens the reaction time to decrease the water treatment expenditures. Photocatalytic destruction kinetics was studied for a non-ionic surfactant, namely, octylphenol ethoxylate (Triton X-100) with hydrogen peroxide in an aqueous medium in reactors with immobilized TiO2. The conditions for achieving a high degree of mineralization of Triton X-100 (84–88% for 4–5 h at C0= 50 mg/dm3) were established in the H2O2/TiO2/UV (λ = 254 nm) system in a reactor with TiO2immobilized on a large-pore ceramic support alongside with its essential advantages as compared to the TiO2/UV system, where the maximum degree of mineralization of Triton X-100 was 2.5 times lower. The possibility of attaining a high degree of mineralization with hydrogen peroxide for Triton X-100 (up to 92% on TOC basis of 2 h) was demonstrated in a quartz reactor with a Degussa P-25 TiO2film on its inner surface at the external irradiation mode (λ = 254 nm) without additional TiO2powder.

Abstract—: Samples of amorphous silicon dioxide (SiO2) were obtained by acid decomposition of mineral raw materials (nepheline). Their physicochemical, acid–base, structural, and surface properties were studied by chemical analysis, potentiometric titration, and by the methods of Parks, Brunauer–Emmett–Taylor (BET), Barrett–Joyner–Halenda (BJH), and others. It was determined that the obtained SiO2samples are almost identical to pyrogenic amorphous silicon dioxide produced from reactive raw materials (pharmaceutical drug Polisorb MP) in content of impurities, pH of the aqueous extract, and pH values of the isoionic point and the zero-charge point and have larger values of specific external surface area and specific pore volume (by a factor of 1.1–1.9 and ~1.4, respectively). Based on the found values of the specific capacity of the adsorption monolayer of the surface of the SiO2samples and the Gibbs free energy change of sorption (ΔG0), it was concluded that the method of their preparation does not significantly affect the physicochemical properties of their surfaces and the mechanism of nitrogen sorption. On the basis of the results obtained, it was assumed that silicon dioxide produced by acid processing of mineral raw materials is promising as an enterosorbent in therapeutic practice.

Purpose: Spinal cord injury (SCI) is a catastrophe that causes disabilities and permanently changes people's lives. The people have to adapt to the loss of self-care ability and may need [...]

Abstract: Alkylphenolpolyethoxylates whose bioresistant metabolites (alkylphenols, short-chain alkylphenolpolyethoxylates and alkylphenoxycarboxylic acids) are compounds with hormonal activity that pose a serious threat to living organisms are among the main types of nonionic surfactants widely used in industry and everyday life. Advanced oxidation processes (AOPs)—in particular, photocatalytic processes—are capable of effectively removing such impurities from an aqueous medium. However, photocatalytic oxidation of some synthetic surfactants with oxygen until their complete mineralization proceeds slowly. The combined use of a photocatalyst and oxidizing agents that are stronger than oxygen contributes to an increase in the degree of mineralization of organic impurities and a decrease in the reaction time compared to those achieved with separate treatment by both methods, which gives rise to the lower cost of water purification and improves the environmental friendliness of the combined process. The photocatalytic processes of degradation of nonionic surfactant octylphenol ethoxylate (Triton X-100) in an aqueous medium by ozone (O3), by ozone and UV radiation jointly (O3/UV), and by ozone and atmospheric oxygen in a TiO2Degussa P-25 suspension (O3/TiO2/UV and O2/TiO2/UV) under UV irradiation with a DB-15 low-pressure mercury quartz lamp (λ = 254 nm) have been studied. The parameters of photocatalytic ozonation have been determined to ensure the nearly complete destruction of Triton X-100 (97% according to total organic carbon). The advantages of photocatalytic ozonation of a Triton X-100 solution in comparison with ozonation, O3/UV treatment, and photocatalytic oxidation with air oxygen are demonstrated.

A population-based study of benzodiazepine users ages 65 and older has found no evidence for a causal link between use of the drug and risk for dementia. Contrary to the [...], * Data from a prospective cohort study of older adults were used to evaluate the association between cumulative exposure to benzodiazepines and cognitive decline. * Contrary to expectations, no increased risk of dementia was found in the group with the highest level of exposure to benzodiazepines, while there was a slightly increased risk of dementia in low- and moderate-exposure groups. * In an analysis that excluded benzodiazepine use in the 2 years prior to a dementia diagnosis, there was no longer a significant risk of dementia or Alzheimer's disease in the low-exposure group.

Abstract: Titanium dioxide, one of the most important photocatalysts for the oxidation of compounds dissolved in water, is active only under ultraviolet irradiation and inactive in the visible spectral region due to its broad bandgap. A promising strategy for the creation of active TiO2samples able to efficiently utilize visible sunlight and thereby to essentially decrease the cost of the photocatalytic treatment of natural and waste water is the introduction of several dopants. The efficiency of nitrogen doped and nitrogen and iron ion codoped titania samples synthesized by the sol-gel method with a bandgap narrowed to 2.59–2.99 eV in the photocatalytic destruction of humic acid (HA) in water (C= 55–60 mg/dm3) with atmospheric oxygen and hydrogen peroxide was studied depending on pH and a radiation source: an SVD-120 mercury quartz lamp (λ > 200 nm) or a GE CMG70 metal halide lamp (λ > 360 nm). The efficiency of doped TiO2samples in the photocatalytic oxidation of aqueous HA solutions depended on the iron content (0–1% of Fe), the used oxidant, pH of the medium, and the irradiation mode. A much higher degree of HA destruction was attained in an acidic medium (pH02.4) as compared to a neutral medium (pH07) in both irradiation modes. The application of hydrogen peroxide increased the degree of photocatalytic HA mineralization in the presence of all the synthesized samples in both irradiation modes as compared to the oxidation with dissolved oxygen and essentially approached the efficiency of synthesized photocatalysts to standard Degussa P-25 TiO2. On the whole, N-TiO2was most active among the synthesized photocatalysts. No clear dependence of the HA destruction degree on the Fe content in the samples (Fe,N-TiO2; 0.25–1.0%) were established at studied destruction parameters. In general, the codoped samples (Fe,N-TiO2) essentially inhibited HA destruction and, in a neutral medium, the inhibiting effect became stronger with increasing iron content in a sample in both irradiation modes. It seems probable that the recombination of photogenerated electron–hole charge carriers was intensified due to the selected method of N-TiO2codoping with Fe3+ions or the range of dopant concentrations.

Abstract: Developing titanium dioxide (TiO2) samples able to absorb and effectively utilize both ultraviolet radiation and visible light will lead to considerable reduction in costs of photocatalytic purification of natural and waste waters. Using the sol–gel method, we synthesized nanoscale titanium dioxide samples doped with nitrogen or co-doped with nitrogen and iron ions, with the samples having a narrower band gap of 2.59–2.99 eV. The synthesized N-TiO2and (Fe,N)-TiO2samples and the standard titanium dioxide Degussa P-25 are compared in terms of their activities in photocatalytic oxidation of aqueous salicylic acid solutions (0.2 mmol/L, pH 4) by dissolved oxygen or hydrogen peroxide upon irradiation with light from a SVD-120 lamp (λ > 200 nm) or a metal-halide GE CMH70 lamp (λ > 360 nm). The relative photocatalytic activity of doped TiO2samples in oxidation of aqueous salicylic acid solutions depends on their iron content (0–1% Fe), the type of oxidant used, and the irradiation conditions. In photocatalytic oxidation with oxygen, samples N-TiO2(λ > 200 nm) and (Fe,N)-TiO2(1.0% Fe) (λ > 360 nm) exhibit the highest degree of mineralization of salicylic acid among the doped TiO2samples, while (Fe,N)-TiO2(0.5% Fe) is the most effective in degradation of salicylic acid by hydrogen peroxide. Using hydrogen peroxide raises the degree of photocatalytic mineralization of salicylic acid in the presence of any of the synthesized samples under both types of irradiation conditions, compared to its oxidation by dissolved oxygen. In addition, the use of H2O2levels off the differences in the activity between synthesized TiO2samples with different doping level of iron that are observed in the O2/TiO2/UV photocatalytic system upon irradiation with UV–visible light (λ > 200 nm), while the extent of salicylic acid degradation in the presence of most active synthesized catalysts is considerably closer to that achieved with the standard photocatalyst.

An integrated approach is applied to reveal fine changes in the surface-normal structure of 1,2-dimyristoyl-sn-glycero-3-phospho-l-serine (DMPS) monolayers at the air–lipid–water interface occurring in a liquid expanded (LE)–liquid condensed (LC) transition. The combination of the Langmuir monolayer technique, X-ray reflectometry, and molecular dynamics (MD) modeling provides new insight into the molecular nature of electrostatic phenomena in different stages of lipid compression. A homemade setup with a laboratory X-ray source (λ = 1.54 Å) offers a nondestructive way to reveal the structural difference between the LE and LC phases of the lipid. The electron density profile in the direction normal to the interface is recovered from the X-ray reflectivity data with the use of both model-independent and model-based approaches. MD simulations of the DMPS monolayer are performed for several areas per lipid using the all-atom force field. Using the conventional theory of capillary waves, a comparison is made between the electron density profiles reconstructed from the X-ray data and those calculated directly from MD modeling, which demonstrates remarkable agreement between the experiment and simulations for all selected lipid densities. This confirms the validity of the simulations and allows an analysis of the contributions of the hydrophobic tails and hydrated polar groups to the electron density profile and to the dipole component of the electric field at the interface. According to the MD data, the dependence of the Volta potential on the area per lipid in the monolayer has a different molecular nature below and above the phase transition. In the LE state of the monolayer, the potential is determined mostly by the oriented water molecules in the polar region of the lipid. In the LE–LC transition, these molecules are displaced to the bulk, and their effect on the Volta potential becomes insignificant compared with the contribution of the hydrophobic tails. The hydrophobic tails are highly ordered in the state of the liquid crystal so that their dipole moments entirely determine the growth of the potential upon compression up to the monolayer collapse.

Background/objectives:: Chungkookjangis a Korean representative fermented soybean food. In this study, we investigated the effect of Korean traditional Chungkookjangcompared with placebo on body composition, dyslipidemia and risk factors for atherosclerosis in overweight/obese subjects. Subjects/methods:: This double-blind, randomized, controlled crossover trial was conducted on 120 overweight/obese subjects, aged 19–29 years. Subjects were randomly divided into a Chungkookjang(n=60) or a placebo (n=60) group. After 12 weeks, the groups were crossed over for an additional 12 weeks. During the intervention period, subjects were asked to maintain their usual diet and activity and not to take any functional foods or dietary supplements. The anthropometric measures, lipid profiles and atherogenic indices were determined at baseline and at the end of each 12-week period. Results:: The anthropometry measurements, percentage body fat, lean body mass, waist circumference and waist-to-hip ratio of women in the Chungkookjanggroup were significantly improved compared with the placebo group. Lipid profiles and high-sensitivity C-reactive protein of women in Chungkookjangwere significantly improved. The atherogenic indices of apolipoprotein B/apolipoprotein A1 decreased in both the placebo and the Chungkookjanggroup, and it also decreased below 0.55 for all the men and women in the Chungkookjanggroup. Conclusions:: In conclusion, these results suggest that supplementation with Chungkookjangmay improve body composition and risk factors for cardiovascular disease in overweight and obese adults.

We have developed two new types of lasers based on quantum-confined semiconductor optical amplifiers with an acousto-optic tunable filter in an external fibre ring cavity. The lasers offer continuous wavelength tuning ranges from 780 to 885 and from 880 to 1010 nm, 20 mW of cw output power, and a tuning rate up to 104 nm s-1 at an instantaneous spectral linewidth less than 0.1 nm.

The Faraday effect induced by an external magnetic field in TbFe_3(BO_3)_4 and TbAl_3(BO_3)_4 borates at a wavelength 633 nm has been investigated. It was found that the terbium subsystem brings the dominant magnetic contribution to the Faraday rotation at low temperatures in borate TbFe_3(BO_3)_4. For both TbFe_3(BO_3)_4 and TbAl_3(BO_3)_4 the magneto-optical coefficients of the terbium subsystem were determined.

Quantum-well superluminescent diodes (SLD) with extremely thin active (AlGa)As and (InGa)As layers and centre wavelengths about 810, 840, 860 and 880 nm are experimentally studied. Their emission spectrum possesses the shape close to Gaussian, its FWHM being 30 - 60 nm depending on the length of the active channel and the level of pumping. Under cw injection, the output power of light-emitting modules based on such SLDs can amount to 1.0 - 25 mW at the output of a single-mode fibre. It is demonstrated that the operation lifetime of these devices exceeds 30000 hours. Based on the light-emitting modules the prototypes of combined BroadLighter series light sources are implemented having a bell-shaped spectrum with the width up to 100 nm.

Input data used in Multi‐Attribute Decision Making (MADM) problems are often perceived to be imprecise by decision‐makers because they are based on expert assessments. As a result, an important step in many applications of MADM is to perform a sensitivity analysis on the input data to help decision‐makers understand how in which regions of the input data space they can be most confident in the recommended decisions and where improved input information is most needed. This paper describes sensitivity analysis procedures which will help decision‐makers examine the robustness of the optimal solution to changes in input parameters in system selection decisions, where the system is made up of components (drilling technologies) that can be combined in many different ways. This paper presents two different sensitivity analysis methodologies. One is a sensitivity analysis for weighting factors of each attribute, and the other is a sensitivity analysis for uncertainty of overall attribute inputs. An application case study of the proposed approach is described to select optimal onshore Environmentally Friendly Drilling (EFD) systems at Green Lake near McFaddin, TX. © 2011 Wiley Periodicals, Inc.

A plasma is regarded as quantum if its macroscopic properties are significantly affected by the quantum nature of its constituent particles. A proper description is necessary to comprehend when collective quantum plasma effects are important. In this paper, the most commonly used microscopic approaches to describe a collisionless quantum plasma are reviewed, together with their related assumptions and restrictions. In particular, the quantum plasma hydrodynamic approximation is analyzed in detail, and the analytical properties of the linear dielectric response function obtained from quantum plasma kinetic theory are investigated. Special attention is paid to what we consider to be the most important problems that have already appeared in the linear approximation and require further studies.

Abstract: A mixed boundary-value problem is solved for a piecewise-homogeneous elastic body with a rectilinear semi-infinite crack on the line where the materials are joined. A rigid patch plate (a reinforcing plate) of specified shape is attached to the upper edge of the crack on a finite interval adjacent to the crack tip. The edges of the crack are loaded with specified stresses. The body is stretched at infinity by a specified longitudinal stress. External forces with a given principal vector and moment act on the patch plate. The problem reduces to a Riemann-Hilbert boundary-value matrix problem with a piecewise-constant coefficient, the solution of which is explicitly constructed using a Gaussian hypergeometric function. The angle of rotation of the patch plate and the complex potentials describing the stress state of the body are found and the stress state of the body close to the ends of the patch plate, one of which is also simultaneously the crack tip, is investigated. Numerical examples are presented that illustrate the effect of the initial force parameters, the length of the patch plate and other parameters of the body on the angle of rotation of the patch plate and the stress state of the body. [Copyright &y& Elsevier]

Presented in this work are the results of investigation aimed at analysis of coordinate distributions for azimuths and ellipticity of polarization (polarization maps) in blood plasma layers laser images of three groups of patients: healthy (group 1), with dysplasia (group 2) and cancer of cervix uteri (group 3). To characterize polarization maps for all groups of samples, the authors have offered to use three groups of parameters: statistical moments of the first to the fourth orders, autocorrelation functions, logarithmic dependences for power spectra related to distributions of azimuths and ellipticity of polarization inherent to blood plasma laser images. Ascertained are the criteria for diagnostics and differentiation of cervix uteri pathological changes.

We have studied superluminescent diodes (SLDs) and semiconductor optical amplifiers (SOAs) based on an (AlxGa1-x)As/GaAs single quantum well structure with an Al content x [?] 0.1 in a 10-nm-thick active layer. Depending on the length of the active channel, the single-mode fibre coupled cw output power of the SLDs is 1 to 30 mW at a spectral width of about 50 nm. The width of the optical gain band in the active channel exceeds 40 nm. Preliminary operating life tests have demonstrated that the devices are sufficiently reliable.

A method of service life tests of SLD-37 quantum-well superluminescent diodes (SLDs), which are widely used in optical coherence tomography, is described and the results of tests are presented. Special attention is given to variations in the emission spectra of SLDs during their aging. It is shown that this method can be used as an incoming test to select processed semiconductor heterostructures with the longest expected lifetime for fabrication of active elements of SLD modules.

Superluminescent diodes (SLDs) with two electrically isolated injection areas based on a single quantum-well GaAlAs/GaAs heterostructure operating at around 825 nm are studied experimentally. It is shown that varying the currents injected through the sections allows these SLDs to produce the cw output power from a few to nearly a hundred milliwatts without changing the spectral bandwidth (about 70 nm).

AbstractIntermediate members of the grossular–andradite and grossular–uvarovite series are known to display anomalous birefringence, which is inconsistent with the ideal cubic space group of garnet Ia3¯d. To determine the reason for such birefringence, the crystal structures of at least 15 samples were refined by different authors including the present ones. The crystals with the value of anomalous birefringence of ?n> 0.001 are normally characterized by partial ordering of the octahedral cations (Al/Fe and Al/Cr for grossular–andradite and grossular–uvarovite series, respectively). This reduces the symmetry to the orthorhombic space group Fdddor even to the triclinic space group I1¯. As is seen from the distribution of occupancies over octahedral sites in the triclinic space group, eight occupancies are grouped into two quartets of similar occupancies, leading to pseudo-orthorhombic crystal structures. The variety of structures with different degrees of pseudo-orthorhombicity is due to the action of the growth dissymmetrization mechanism. Simulations of the optical indicatrix in the point-dipole approximation confirm cation ordering as the main cause of the anomalous birefringence.